in map castaway the rotten satchel did not drop

like in the title the map boss in the castaway unique map dident drop a satchel to blow up the map so i could not get map completion
i was in the party with my friend who opened the map. he died and could not go in
i dont know if thats the issue that caused this

just had this same issue, I the instance owner died at the end of the boss fight and my party member could not pick up the satchel charge to complete the map. very disappointing

Same thing happend here